Fish is great. For those wondering what advantages is has over zsh+ohmyzsh, I can say is that by default it provides most the functionality you want without having to install/tweak anything. Git support is built in (you get a nice git prompt) there's syntax highlighting, amazing history completion, predictive commands, man page completions... and so on. To try it on linux, just install fish and then run "fish", to get back to to bash/zsh just "exit"

Only problem is it's not POSIX so there is some weirdness in command substitution, logical operators and stuff. So you still script in sh.

If I'm motivated enough to download and install a shell, why wouldn't I just clone Prezto and change one config file to turn on syntax highlighting and git support? Especially when it doesn't bring any "weirdness in command substitution" and I get the great zsh expansions and completions?

Anyways, I'll try it out (why not?) but the benefit to me wasn't clear from the page, and even with your direct clarification here I'm seeing more downsides than zsh + Prezto and not a significant upside.